"So, does drug testing prevent or inhibit student drug use? Our data suggest that, as practiced in recent years in American secondary schools, it does not. That is different from saying that it could not under any circumstances. The two forms of drug testing that are generally assumed to be most promising for reducing student drug use—random testing applied to all students (and, therefore, also likely applied to those in any extracurricular activities, which may come close to encompassing all students), and testing of athletes—did not produce encouraging results."

Source

Yamaguchi, Ryoko; Johnston, Lloyd D.; and O’Malley, Patrick M., "Drug Testing in Schools: Policies, Practices, and Association With Student Drug Use," Institute for Social Research (Ann Arbor, MI: The University of Michigan, 2003), p. 16.
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